Whether this or future Earth Days help solve any particular environmental problems won’t matter a bit, unless we tackle the biggie—climate change. Bill McKibben, who sounded the alarm two decades ago with his landmark book The End of Nature, reviews the damage and points the way forward. The x-factor in preventing catastrophe, he says, will be whether the American public—with its financial and cultural power to move mountains—sort of gets it, or really gets it.

Let us take as our text for this sermon the words of James Hansen, NASA climatologist and as close to a prophet as the last few decades have raised up: If the Earth continues to heat at its current rate, he said earlier this year, it would “imply changes that constitute practically a different planet…We can’t let it go on another 10 years like this. We’ve got to do something.”

In the last year, the onrushing tide of ecological—and resulting economic—damage has become very clear. What was until recently mostly theoretical now has a name and a face. Let’s call her Katrina—wild, vengeful and ruinous. Let’s call her Wilma, recording the lowest barometric pressure ever seen in the Atlantic. Let’s call her Zeta, still spinning in the Atlantic on New Year’s Day, the last in the endless string of tropical storms that broke every record, and with them, at long last, the complacency about environmental threats that has dominated our politics for at least a decade.

There are, obviously, all kinds of ecological perils out there. We’ve overfished our seas, we’ve overcut our forests. Fresh water is beginning to run short, and species are disappearing at a rapid rate. You can come up with a long and troubling list, including the disturbing fact that most of the world’s people are so poor they can barely summon the energy to care about the larger world. But it’s becoming very clear that the overriding, overpowering summation of them all is climate change—lose this battle and it won’t matter if we win all the others, because it’s simply so much bigger, and connected to everything else. The best guess of scientists is that we will, on our present course, make the planet about 5° C warmer by century’s end. That’s warmer than it’s been in a long time—since well before our ancestors climbed down from the trees.

More for Earth Day 2006

The APR/MAY 2006 issue of Seed offers seven new ideas to curb global warming. To get them all, click here.

For web-only interviews with activists, scientists and policymakers, who give their assessments and outlooks on our planet, click here.

And climate change is also the perfect metaphor for the larger task we face, since conquering it will mean changing almost everything about the daily life of most people in the developed world. Actually, “conquering” isn’t even on the menu any more; the best hope is to keep things merely miserable, not downright catastrophic. And that will be a tall order—the atmospheric concentration of carbon dioxide, rising ever since the Industrial Revolution kicked off two centuries ago, has been spiking the last few years. Scientists say that’s because the human-induced warming has begun to cause the planet’s basic systems to change: white, reflective ice melts at the poles, replaced by blue, absorptive water, for instance, which is accelerating the warming. Or thawing permafrost frees vast stores of trapped methane, now bubbling up through the Siberian tundra. Earlier this year the great British scientist James Lovelock, father of the Gaia theory of Earth self-regulation, announced he thought the planet had passed a tipping point, and that it might be too late to stave off the worst. “Billions will die,” he predicted.

Others are more hopeful—hopeful at least that if we start doing the right thing fast we might still make a substantial difference. So it’s time to figure out what we might do, how we might do it—and who the “we” might be.

Let’s begin with the changes we need to make. Some are technological, and the good news is that the technology, increasingly, is there. Solar and wind power aren’t a green fantasy—they’re the fastest-growing sources of electric generation around the world. My Honda hybrid, chugging along at 55 miles per gallon, is already old technology. In February, Peugeot and Citroën came out with diesel hybrids capable of 80 miles per gallon. Germany and Japan have installed hundreds of thousands of solar panels to power homes and businesses. But all this good news is still modest—perhaps 3% of power in the world comes from real renewables. Switching in time will be a massive task, especially since many of the power plants on the drawing board in the US are old-fashioned coal stations.

And that’s here. The real growth is coming in China and India, which are quickly learning the joys of fossil fuel. The Chinese add the electric generating capacity of southern California annually, almost all of it powered by coal. Without something like the Kyoto Accord to force the rich world to subsidize an entirely different kind of energy industry in the fast-developing world, there’s absolutely no way to even imagine meeting Hansen’s 10 year ultimatum.

So the real question may be: What constellation of forces might shake up the American political system enough to provoke real, deep change? The contenders include:

old-line environmental groups, like the Sierra Club or the Natural Resources Defense Council. And, indeed, they’re doing more and more all the time—but their resources are spread thin across dozens of battles (like last year’s miraculously successful effort to save the Arctic National Wildlife Refuge).

an emerging youth movement: There are signs on many college campuses that students are finally figuring out their future has been mortgaged, and that they’d like to start paying off the note. Energy Action, headed by Yale dropout Billy Parish, has been putting together coalitions across the country that are shaking up campus energy use. But it’s not the ‘60s anymore, so it’s not clear what sort of tactics might attract enough attention to generate massive change.

religious environmentalists have been in the news lately, partly because they’re an unexpected development. The deep bond between conservative politicians and the churches that dominate most of red-state America has helped keep them focused on the world to come. But a growing number of evangelicals are pointing out that, no matter what you think about creation (or creationism), de-creation is a bad plan. They’re a wild card that may have impact in unexpected places.

corporate environmentalism is unexpected too, and also in its infancy. But it may be for real. Companies like BP, pressed by a European public far more educated on green issues than Americans are, have begun to make real changes in their investments. In this country, groups like Ceres have alternated carrot and stick, convincing boards of directors to plan for their exposure to the causes and the effects of climate change. And oh yeah—the insurance industry got a bit of a wake-up call this hurricane season, too.

celebrity environmentalism is always a two-edged sword, since people tend to dismiss ditzy Hollywoodism. But what’s changing, in part thanks to activists like Laurie David and her Virtual March against global warming, is this: The sharp comics, people like Jack Black and Will Ferrell, are beginning to convince the less-engaged that caring about global warming is cool, just as Jon Stewart has made politics interesting to a new audience. Politicos don’t worry much about angry shouting—but when the people start to laugh, watch out.

There are other trends that offer some real hope: Increasingly, for instance, Americans are starting to care about things like local food. That’s good for the neighborhood farmer, and good for the taste buds, but it also helps the atmosphere: to bring a single calorie of iceberg lettuce from California to London takes 127 calories of fossil energy. It’s the kind of trend that might accelerate, if indeed we turn out to be reaching “peak oil,” the point where petroleum starts getting steadily scarcer and exponentially more expensive. In that case, a world where it’s always summer sometime, where we import everything we need, might start making less sense.

In fact, at the state and local level impressive signs of good sense are starting to break out: California is trying to regulate the auto industry since Washington has punted; seven Eastern states have formed a Kyoto-lite compact all their own. There’s a kind of arch of common sense that goes up the coast and across the northern Midwest—the policies adopted in these blue states are edging closer to the European norm, even as the country as a whole shifts ever more towards total deregulation of the energy industry. The city of Portland has actually managed to reduce its carbon emissions toward 1990 levels—and what do you know, its economy is booming. Perhaps that green common sense will spread: Salt Lake City, for instance, is emerging as another bastion of carbon activism. But head-in-the-sandism can be found everywhere too: Ted Kennedy may be the most liberal member of the Senate, but he’s fighting to derail a windfarm planned for five miles off Cape Cod.

What this mixed bag—these slow-but-promising beginnings—show is that we sort of get it. We’ve awakened to the idea that there’s a spot of trouble, that we better start changing. A little. But we don’t get it get it. We haven’t figured out that, unless we make this our one and only priority for a generation, the change will come too slowly if at all. Listen to the man with the computer model. We don’t have another 10 years. Now.